422 



THE FARMERS' REGISTER. 



twelve segments. Its head is rather brownish, 

 and it has six leet situate near the head — this 

 distinguishes it Crom a caterpillar.* In the grub 

 state it continues three years, which accounts for 

 its destroying turnips, seeds, and corn crops, on 

 the same piece of ground successively. It then 

 emerjres in the shape of a beetle, the distinguish- 

 ing characteristic of which is, that, when taken 

 by the posterior exiremiiy, it depresses, and then 

 suddenly elevates, its head and ihorax, and gives 

 a sounding click, hence it has been placed 

 amongst the click beetles, and is called the Cata- 

 phagus lineatus. The beetle is about /our lines 

 long ; color grayish-black ; the wing cases have 

 stripes of gray arranged longitudinally. 



Its ravages are confined to the grub slate, and 

 it feeds on the roots oC the turnips when they are 

 from lour to eight weeks old. I have seen as 

 many as six wire-worms attached to the ror>t of 

 a single plant. Their presence may be delected 

 by the liillingol" the leaves of the plant, and then 

 assuming a dark deadly green. The insects eat 

 the root at a depth of one or one and a half iuch, 

 and sometimes gnaw throuo'h the whole root, and 

 the turnip of course dies. Occasionally a whole 

 field, though more generally a portion of a field, 

 subject to it will go ort'. 



Cure there is none, that I am aware ofj but 

 much may be done by way of prevention. I 

 have before me several cases noted down where 

 a crop of potatoes, taken belbre the turnip crop, 

 has effectually tended to prevent the attack. I 

 will oii'er one striking instance furnifhed me by a 

 personal friend. A trapezium-shaped field was 

 in 1833 sown with turnips, exceptiuir the angular 

 side, which was potatoes, the turnips went off" by 

 the wire- worm. In 1837 the field was again in tur- 

 nips. The part which was potatoes in ls33 car- 

 ried a good crop of turnips, and were uninjured 

 except the heatlland, ivhich /ml not been potatoes, 

 and where the turnips went off, as iheydid in the 

 other parts of the field which had been turnips 

 in 1833, I have heard of the wire-worm injuring 

 potatoes, and of this I have no doubt, for I have 

 lound them half buried in the potato, but did ihey 

 ever leed on them? I confined five wire-worms 

 in an earthen jar wiih soil, and gave them a heal- 

 thy potato. Not a particle of the potato was 

 eaten, and the insects all died. I can easily con- 

 ceive that, either in the agonies of death or in 

 search of Ibod, a wire-worm might burrow 

 through a potato the same as through a clod of 

 earth, but that they ever leed on it I cannot be- 

 heve without belter evidence than I have had 

 hitherto. VVhether it is that a potato crop actually 

 starves the wire-worm from want of Ibod, or whe- 

 ther there is some peculiar effluvia from the tubes 

 or haum I cannot say, but the fact is well known 

 by several eminent agriculturists I can name. 



4. There is a too well known disease to which 

 turnips are liable, called " fingers and toes." The 

 fibres or tap root of the turnip, or both, thicken, 

 and knobs of every conceivable shape are formed ; 

 tiiese swell and crack, and of course begin to pu- 

 trefy ; this goes on, and the plants disappear ra- 

 pidly until a field of promising turnips are not 

 worth five shillings per acre. Those plants with 



" Ail caterpillars, properly so called, have six feet 

 in the situation alluded to. The writer means that it 

 possfssps these solely, there bein^ no ahilominal feet 

 i? i,ii caterpillars. — Ed. Far. Mug. 



the most fibrous roots stand the attacks the best. 

 Every conceivable variety of opinion has been 

 mentioned as the cause of this disease. I shall 

 not even advert to them, but give simply the re- 

 suits of my own observation. Knowing certain 

 fields to be subject to attacks, I have narrowly 

 watched the progress of plants from sowing time 

 forwards. T'he first thing I observed belbre they 

 were fit I'ov hoeing, were several ash-gray colored 

 flies resembling the house-fly, but somewhat 

 smaller. On examining the nervures of the 

 leave^!. I discovered eggs of the flies resembling 

 the "fly-blows" of the MuscidcB. In a week 

 maggots were formed, which crawled into the 

 ground and attacked ihe root of the plant. A 

 puncture, however slight, will cause a flow of 

 sap 10 the place, and a tubercle or excrescence is 

 lormed. In this the maggot fastens. I have 

 detected six or eight at one plant ; these continu- 

 ally gnaw it until they either destroy it or change 

 into pupaj, and the plant putrefies and dies. Some- 

 times only one fibre is attacked and then the 

 plant survives. They emerge Irom the pupa and 

 assume the fly Ibrm, some in the same season, 

 but more in ihe ensuing year, to spread again the 

 work of destruction. I believe it is the u'lnthomya 

 brassicce ol' Bouche. The length of the fly is 

 about three lines, color ash-gr,iy. Male fly an 

 indistinct black mark on the back. The wings 

 are transfiarent. I have taken them and bred 

 them, and having watched every stage of their 

 existence, I am, therefore, clear as to the connex- 

 ion of the insect with the disease. 



A prevention to their ravages I have found in 

 a summer fallow. It seems to banish the parent 

 flies, which otherwise are of still habits, whereas 

 the frequent successions of turnips, attended as 

 they are by a great mass of decomposed vegeta- 

 ble matter, encourage the flies and perpetuate 

 the evil. 



5. Another little depredator, within the epider- 

 mis of the exposed portion ol the bulb of the tur- 

 nip and causing a little knob to rise on the bulb, 

 appears amongst the ^insects feeding on turnips. 

 In its existing form it is a maggot and the larvse 

 of one of the CynipidcB; I believe it is the Cynips 

 brassicoi. The injury, however, it effects is so 

 trifling as scarcely to be worth naming, for the 

 plants affected by it are often the finest in the 

 field. I know of no remedy, nor indeed of any 

 method ever aitempted to destroy it. 



6. The last noxious insect affecting turnips, to 

 which I shall allude, is the plant-louse, jlphis 

 brass'iccE. To descrilie it is unnecessary — mulii- 

 rudes, nay myriads, assailed the crops in 1836. 

 They feasted by thousands on every leaf and de- 

 prived it of its juices. The leaves rose in blisters, 

 and turned a sickly pale yellow, the bulbs were 

 arrested in their growth, and most serious injury 

 was -done to the crops. In October they took 

 wing, and were to be seen in clouds which filled 

 the air, and raised much annoyance by getting 

 into the eyes, mouth, &c. Providentially they 

 were accompanied by large numbers of the lady- 

 birds, ( Coccme/Zidce,) which thinned them consi- 

 derably. I know of no successful experiment be- 

 ing tried to prevent or cure. Applications of to- 

 bacco, &c., may answer for a gardener, but it is 

 mere theory to recommend it lo the liarmer who 

 has, perhaps, his halt-thousand acres of turnips, 

 Let encoiiragonieni be given to the increase nl 



